| Ambrosia trifida | |
|---|---|
 | |
Scientific classification  | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Asterids |
| Order: | Asterales |
| Family: | Asteraceae |
| Genus: | Ambrosia |
| Species: | A. trifida |
| Binomial name | |
| Ambrosia trifida | |
| Synonyms [2] | |
| |
Ambrosia trifida, the giant ragweed, is a species of flowering plant in the family Asteraceae. It is native to North America, where it is widespread in Canada, the United States, and northern Mexico. [1]
It is present in Europe and Asia as an introduced species, and it is known as a common weed in many regions. [3] Its common names include great ragweed, Texan great ragweed, giant ragweed, tall ragweed, blood ragweed, perennial ragweed, horseweed, [4] buffaloweed, and kinghead. [5]
This is an annual herb usually growing up to 2 m (6 ft 7 in) tall, but known to reach over 6 m (20 ft) in rich, moist soils. The tough stems have woody bases and are branching or unbranched. [5] Most leaves are oppositely arranged. The blades are variable in shape, sometimes palmate with five lobes, and often with toothed edges. The largest can be over 25 cm (9.8 in) long by 20 cm (7.9 in) wide. They are borne on petioles several centimeters long. They are glandular and rough in texture. The species is monoecious, with plants bearing inflorescences containing both pistillate and staminate flowers. The former are clustered at the base of the spike and the latter grow at the end. The fruit is a bur a few millimeters long tipped with several tiny spines. [1] [6]
This species is well known as a noxious weed, both in its native range and in areas where it is an introduced and often invasive species. [7] [8] [9] It is naturalized in some areas, and it is recorded as an adventive species in others. [3] It grows in many types of disturbed habitat, such as roadsides, and in cultivated fields. Widespread seed dispersal occurs when its spiny burs fall off the plant and are carried to new habitat by people, animals, machinery, or flowing water. The plant is destructive to native and crop plants because it easily outcompetes them for light. [5]
Herbicide resistant giant ragweed populations were first identified in the late 1990s. [10] Across much of the midwestern United States, populations resistant to group 2 (ALS-inhibitors) and group 9 (glyphosate) are present, though resistant to multiple herbicide modes of action has not yet been documented. There remains concern that herbicide resistance is more widespread than documented and many states like Minnesota offer free screening of giant ragweed for herbicide resistance [11] For chemical control, use of group 4 (2-4D) and group 10 (glufosinate) are effective. [10]
Also, interest is great in preventing the spread of this plant because its pollen is a significant human allergen. [12] It is one of the most familiar allergenic ragweeds, and residents of different regions begin to experience allergic symptoms as the plant spreads into the area. [13]
Native Americans had a number of uses for the plant as traditional medicine. The Cherokee used it as a remedy for insect stings, hives, fever, and pneumonia, and the Iroquois used it to treat diarrhea. [14] The plant is suspected to have been domesticated by Native Americans as a oily seed crop as early as 1200BCE. This means it may have been a member of the Eastern Agricultural Complex. [15]
Giant ragweed has been used successfully as a compost activator and an ingredient in sheet mulch gardens. [16]
Ragweeds are flowering plants in the genus Ambrosia in the aster family, Asteraceae. They are distributed in the tropical and subtropical regions of the Americas, especially North America, where the origin and center of diversity of the genus are in the southwestern United States and northwestern Mexico. Several species have been introduced to the Old World and some have naturalized and have become invasive species. In Europe, this spread is expected to continue, due to ongoing climate change.
Xanthium (cocklebur) is a genus of flowering plants in the tribe Heliantheae within the family Asteraceae, native to the Americas and eastern Asia and some parts of south Asia.
Ambrosia artemisiifolia, with the common names common ragweed, annual ragweed, and low ragweed, is a species of the genus Ambrosia native to regions of the Americas.
Ambrosia dumosa, the burro-weed or white bursage, a North American species of plants in the family Asteraceae. It is a common constituent of the creosote-bush scrub community throughout the Mojave desert of California, Nevada, and Utah and the Sonoran Desert of Arizona and northwestern Mexico.
Ambrosia acanthicarpa is a North American species of bristly annual plants in the family Asteraceae. Members of the genus Ambrosia are called ragweeds. The species has common names including flatspine bur ragweed, Hooker's bur-ragweed, annual burrweed, annual bur-sage, and western sand-bur. The plant is common across much of the western United States and in the Prairie Provinces of Canada.
Amaranthus tuberculatus, commonly known as roughfruit amaranth, rough-fruited water-hemp, tall waterhemp, or common waterhemp, is a species of flowering plant. It is a summer annual broadleaf with a germination period that lasts several months. Tall waterhemp has been reported as a weed in 40 of 50 U.S. states.
Ambrosia chamissonis is a species of ragweed known by the common names silver burr ragweed, silver beachweed and (silver) beach bur(r).
Ambrosia psilostachya is a species of ragweed known by the common names Cuman ragweed and perennial ragweed, and western ragweed.
Ambrosia chenopodiifolia is a species of ragweed known by the common names San Diego bursage and San Diego bur ragweed. It is native to the Mexican states of Baja California and Baja California Sur, as well as to Orange and San Diego Counties it int US State of California. It is a member of the coastal sage scrub plant community.
Ambrosia confertiflora is a North American species of ragweed known by the common name weakleaf bur ragweed.
Ambrosia pumila is a rare species of herbaceous perennial plant known by the common names San Diego ragweed and San Diego ambrosia. It is native to far southern California, Baja California, and Baja California Sur. It grows in floodplains and open grasslands in proximity to wetland areas.
Ambrosia tomentosa, the skeletonleaf bur ragweed, silverleaf povertyweed, or skeleton-leaf bursage, is a North American species of perennial plants in the family Asteraceae.
Xanthium spinosum is a species of flowering plant in the aster family known by many common names, including spiny cocklebur, prickly burweed and Bathurst burr. This species is part of the genus Xanthium that encompasses 25 different species of flowering plants of the daisy family, Asteraceae, and sunflower tribe.
Ambrosia deltoidea is a North American species of flowering plant in the family Asteraceae known by the common names triangle bur ragweed, triangle bursage, and triangleleaf bursage.
Ambrosia linearis is a species of flowering plant in the family Asteraceae known by the common names streaked bur ragweed, Colorado bursage, linear-leaf bursage, and plains ragweed. It is endemic to east-central part of the state of Colorado in the United States, where it occurs in Elbert, Pueblo, El Paso, Cheyenne, Crowley, Kiowa and Lincoln Counties.
Damasonium minus is a species of flowering plant in the water-plantain family known by the common names starfruit and star-fruit. It is native to Australia, where it occurs everywhere except the Northern Territory. It is perhaps best known as an agricultural weed. It is a major weed of Australian rice crops.
Ambrosia bidentata, the lanceleaf ragweed, is a North American species of plants in the family Asteraceae. It is native to the central and eastern parts of the United States, primarily the Mississippi Valley and the eastern Great Plains.
Ambrosia cordifolia, called the Tucson bur ragweed, is a North American species of plant in the family Asteraceae. It is native to northern Mexico and the State of Arizona in the United States.
Ambrosia grayi, the woollyleaf bur ragweed, is a North American species of plants in the family Asteraceae. It is native to the west-central part of the Great Plains of the United States, in the states of Nebraska, Kansas, Colorado, New Mexico, Oklahoma, and Texas.
Weed science is a scientific discipline concerned with plants that may be considered weeds, their effects on human activities, and their management "a branch of applied ecology that attempts to modify the environment against natural evolutionary trends.".
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